Kinetics of piretanide absorption from the gastrointestinal tract.

In a recent report, it was shown that the loop diuretic piretanide is rapidly absorbed after placement of a piretanide solution in the duodenum, while the rate of absorption is definitely slower when the drug is instilled into the ascending colon (5). When piretanide is instilled into the stomach, the absorption process does not differ significantly from that after placement in the duodenum, neither with respect to amount nor rate (5). However, it was not clear from this study whether piretanide is directly absorbed from the stomach or rapidly released into the duodenum.